Attorney General Merrick B. Garland offered a fiery defense of the Justice Department’s investigation of Hunter Biden on Wednesday, telling a House committee he was “not Congress’s prosecutor” — and would not reveal details of the inquiry no matter how much pressure lawmakers applied.
During a grueling and combative hearing before the House Judiciary Committee, Mr. Garland repeatedly refused to answer questions about internal deliberations or offer explanations for decision-making in the investigation, or the two federal indictments of former President Donald J. Trump.
House Republicans view Mr. Garland as a linchpin as they seek to bolster an impeachment inquiry that is grounded, thus far, in inconclusive evidence that President Biden profited from his son’s business dealings. They have suggested he also might face impeachment, or contempt charges, for not fully answering their questions or providing access to documents and witnesses they have demanded.
Many of the claims and insinuations leveled against Mr. Garland by Republicans — that he is part of a coordinated Democratic effort to shield the Bidens and persecute Mr. Trump — were not supported by fact. And much of the specific evidence presented, particularly the testimony of an investigator who questioned key decisions in the Biden investigation, was given without context or contradictory information.
Mr. Garland, a former federal appellate judge known for his circumspect and soft-spoken demeanor, took a more aggressive approach than during past hearings. Countering their claims, he denounced escalating threats against prosecutors, including the special counsel Jack Smith, and F.B.I. agents by Trump supporters, which have prompted significant increases in security.
“Singling out individual career public servants who are just doing their jobs is dangerous — particularly at a time of increased threats to the safety of public servants and their families,” said Mr. Garland, who later reacted angrily when a Republican committee member called out a career prosecutor by name.
“We will not be intimidated,” he added. “We will do our jobs free from outside influence. And we will not back down from defending our democracy.”
It was Mr. Garland’s first appearance before the committee since Mr. Smith brought two criminal indictments against Mr. Trump and a plea deal for Hunter Biden collapsed over the summer.
Mr. Garland’s appearance took place at what had been, in years past, a routine oversight hearing that would typically center on policy, crime, law enforcement initiatives and civil rights — issues that were largely jettisoned for attacks by Republicans and counterattacks by Democrats.
Republican committee members had signaled that they would grill Mr. Garland about his role in the later stages of a five-year investigation into Hunter Biden. It appeared to be nearing an end this summer until it imploded in July over the terms of the plea deal between Mr. Biden and the U.S. attorney for Delaware, David C. Weiss.
Republicans focused on a claim by a former Internal Revenue Service investigator, Gary Shapley, who said Mr. Weiss had suggested that he was being blocked from fully investigating the case of Mr. Biden’s taxes by being denied the power to independently pursue charges in jurisdictions outside Delaware. (Mr. Weiss and several other investigators in the case have denied the claim.)
On Wednesday, they homed in on one of the biggest unexplained questions: why Mr. Weiss requested to be appointed special counsel in August after Mr. Garland told a Senate committee this year that as the U.S. attorney in Delaware, Mr. Weiss had all the authority he required — and had never asked him for a change in status.
“Did you ask him what had changed, that made him now need to be made a special counsel?” asked Representative Dan Bishop, Republican from North Carolina.
In response, Mr. Garland cited a promise he had made to senators during his confirmation in 2021 — that he would not interfere with the work of Mr. Weiss to avoid any appearance that he was influencing an investigation into his boss’s son.
“I have kept that promise,” he said. “The way to not interfere is to not investigate an investigation.”
The theory that President Biden intervened to protect his son, widely trumpeted by House Republicans and amplified by conservative news media, is a prime motivator behind the impeachment inquiry begun by Speaker Kevin McCarthy under pressure from the right flank of his party.
Republicans see Mr. Garland as a critical link, even though he has taken steps to insulate himself from the case, including by reappointing Mr. Weiss, a Trump appointee. Similarly, officials say, he has virtually cut off communications with the White House since the department began investigating Mr. Trump.
“As the president himself has said, and I reaffirm here today: I am not the president’s lawyer,” he said in his opening statement.
Over the past week, Representative Jim Jordan, Republican of Ohio and the chairman of the Judiciary Committee, has increased the pace and scope of his demand for access to documents and officials, including Mr. Weiss and his deputies, claiming they are fundamentally necessary for his committee to fulfill its oversight function.
The department has thus far refused to comply, citing laws and regulations that prevent it from disclosing details of open investigations, prompting Thomas Massie, Republican of Kentucky, to suggest Mr. Garland be held in contempt of Congress.
In response, Representative Eric Swalwell, Democrat of California, pointed out that Mr. Jordan, a close ally of Mr. Trump, was one of four Republicans to defy subpoenas issued by the House committee investigating the Jan. 6 attacks when Democrats were in charge.
Republicans have peppered Mr. Garland with a wide range of questions during his other recent appearances, but they kept tightly to the Hunter Biden inquiry this time.
Several times Mr. Garland was asked about his role in the two federal indictments of Mr. Trump — and whether he had personally approved it at the request of Mr. Biden, as Mr. Trump has claimed without providing evidence.
“No one has told me to indict,” he said. “In this case the decision to indict was made by the special counsel.”
The contrast between Mr. Jordan and Garland, in tone and volume, was particularly striking. Time and again, the congressman rattled off rapid-fire assertions about White House interference in the Hunter Biden investigation, without offering concrete evidence to support his charges.
Mr. Garland, who spent a week preparing for the onslaught he faced, selected his words cautiously, refusing to offer much beyond what is already in the public record.
His simmering frustration boiled over during one extraordinary exchange after Representative Jeff Van Drew, a New Jersey Republican, said that the department had discriminated against Catholics by sending F.B.I. agents into churches.
“The idea that someone with my family background would discriminate against any religion is so outrageous — absurd!” shouted Mr. Garland, who is Jewish, referring to his family’s experiences in the Holocaust.
Mr. Jordan repeatedly accused the Justice Department of slow-walking potential felony tax charges into Hunter Biden because the statute of limitations has since expired. But the F.B.I. continues to investigate the president’s son, including whether he violated the Foreign Agents Registration Act, commonly known as FARA, in his business dealings abroad.
The hearing was as much an exercise in political combat as an exchange of information. Mr. Jordan, speaking in a shout for most of the hearing, established the tenor from the start, declaring in his opening statement that “the fix is in!”
Representative Jerrold Nadler of New York, the ranking Democrat on the committee, shot back in his opening remarks, saying “extreme MAGA Republicans have poisoned our vital oversight work” in an effort to distract from the multiple indictments of Trump.
Mr. Garland, whose voice was reduced to a ragged whisper after hours of constant back and forth, enjoyed only brief moments of respite when Republicans and Democrats on the committee turned their attention on one another.
When Matt Gaetz, the bellicose Republican congressman from Florida, began a blistering attack on the attorney general, Representative Steve Cohen, Democrat of Tennessee, raised the Justice Department’s sex-trafficking investigation into Mr. Gaetz that, ultimately, resulted in no charges.
“Wasn’t there an investigation of Mr. Gaetz, and you did not prosecute him?” asked Mr. Cohen, suggesting that the decision to not bring charges proved the government’s impartiality.
“The department does make comments about its investigations,” Mr. Garland said.
Charlie Savage, Adam Goldman and Luke Broadwater contributed reporting.